Fuel metering system



July 28, 1959 BITTORF FUEL METERING SYSTEM Filed May 6, 1957 IN VENTOR IRVIN BITTORF' CORBETT, MAHONEY & M LLER, ATTYS.

BY MJTTORNEY United States Patent Ofifice 2,896,852 Patented July 28, 1959 FUEL METERING SYSTEM Irvin Bittorf, Columbus, Ohio, assignor of one-half to Earl Bougher, Columbus, Ohio Application May 6, 1957, Serial No. 657,443

Claims. (Cl. 2372) My invention relates to a fuel metering system. It has to do, more particularly, with a fuel metering system associated with a zone heating control system.

Zone heating systems are now in use in buildings, such as apartment buildings or other buildings having various tenants, which have a plurality of separate zones or units to be heated through a common gas or oil fired furnace. Obviously, it is desirable to have independent controls for each zone to be heated, because of the various heat requirements of the tenants, and this is common practice. However, it would also be desirable to know how much fuel is used in heating each zone so that the tenant could be charged accordingly instead of being charged a standard fee which is charged to all tenants or an estimated fee based on the size of the zone used by i the tenant.

It is the object of the present invention to provide a fuel metering system for a zone heating system using a common heating unit whereby the proportionate quan- 'tities of fuel utilized by each zone to satisfy the heat requirements thereof may be metered and recorded so that the user of each zone'can be charged for the fuel used for heating that particular zone and only for the fuel used for that zone.

Various other objects will be apparent. According to this invention, my metering system is embodied in a zone heating system comprising a central heating furnace, either gas or oil fired, having con- -duits for supplying heating medium to the individual zones to be heated. Associated with the heat supply conduits leading to the various zones are heat control valves operable to control the flow of heating medium to the various zones in accordance with the heat demands "'in such zones. According to my invention, fuel is supplied to the furnace by means of a single manifold burner conduit which is provided with separate inlet branches corresponding in number to the number of zones to be I; dividual controls located in each heat zone.

Positioned in each inlet branch ahead of the fuel control valve thereof is a fuel recording meter for measuring and recordingthe amount of fuel flowing through each of the inlet branches to the furnace to supply the heat demands of each respective heat zone.

' In the accompanying drawing, I have shown for illus- J trative purposes only one example of my invention but it isto be understood that details of the system may vary 'without departing from basic principles.

In this drawing: the figure is a diagrammatic view 1 showing the fuel metering system of my invention associated with a zone control heating system of the hot --air type.'

With reference to the drawing, I have illustrated my invention associated with a zone heating system of the hot air type and in which the heated air issupplied by means of a gas fired furnace. However, as previously indicated, my inveniton is not limited to this particular type of heating system.

In the drawing, the gas furnace is illustrated at 10 and is provided with the main gas burner 11 to which the gas conduit 12 leads; A pilot burner 13 is associated with the main burner 11 and receives its supply of gas through a line 14. A partition 10 separates the furnace 10 into a combustion chamber and hot air chamber be:- low and above the partition respectively. A flue 10b is connected to the combustion chamber.

The furnace 10 may heat various zones but is illustrated as being used for heating two independent zones which are designated as Zone 1 and Zone 2. This furnace is of the usual type and is provided with the usual means for supplying heated air to the two zones, the furnace itself being shown merely diagrammatic since its specific structure is not important to this invention. A duct 21 for heated air leads from th furnace 10 to Zone 1 and duct 22 for heated air leads from the furnace 10 to the Zone 2. A motor controlled damper valve 23 is provided for controlling the flow of heated air from the furnace 10 through the duct 21 and a similar motor controlled damper valve 24 is provided for controlling the flow of heated air from the furnace 10 through the duct 22. The damper valve 23 is controlled by linkage 25 from an electric motor 26 and the damper valve 24 is controlled by linkage 27 from an electric motor 28. The

lmotors 26 and 28 are controlled independently by the usual zone heating controls illustrated diagrammatically at 29 and 30, respectively. The controls 29 are actuated by a thermostat 31 in the Zone 1 and the controls 30 are actuated by a thermostat 32 in the Zone 2.

The fuel metering system of this invention is shown in the drawing as comprising a manifold 40 which has a main chamber 38 with an outlet 39 connected to the main burner supply conduit 12. Leading into the main chamber 38 of the manifold 40 is a branch fuel line 41 and a branch fuel line 42 which are provided for supply- 7 ing fuel for heating the respective Zones 1 and 2. Obviunder the pressure of fuel forced into the manifold chamber 38 through the respective inlet branches 41 and 42. These check valves prevent back-feed from the manifold chamber 38 into any inlet branch line when the other is open for supplying fuel into the manifold. If'both are open. at the same time, the pressure at the two inlets will be balanced and there will be no backfeed into either.

The inlet branch 41 is controlled by an electro-responsive device illustrated as a solenoid-actuated flow control valve '51 and the branch 42 is controlled by a similar valve 52. Directly ahead of the valve 51 there is connected to the line 41 a small line 47 which leads to a small'supply chamber 48 provided in the wall of the manifold member 40. Similarly, directly ahead of the valve 52 there is connected a small line 49 which leads to the chamber 48. The line 14 for the pilot burner 13 connects to this chamber 48 and it will be obvious that gas will be supplied in equal amounts from both the lines I 41 and 42 to keep the pilot burner '13 operating. Thus,

the amount of fuel supplied for operating the pilot burner r 3 13 will be received in equal amounts from the lines 41 and 42 which supply fuel for the two zones.

In advance of the point of connection of the pilot line 47 to the inlet branch line 41 is a pressure regulator 61. Similarly, in the line 42, in advance of the connection of the line '49 to the branch 42, there is a pressure regulator '62. These pressure regulators are set to obtain equal pressure in the inlet branch lines 41 and 42 at the valves 51 and 52. Ahead of the pressure regulator 61 in the line 41 is a meter 71 and ahead of the pressure regulator 62 in the line 42 there is a meter 72. These meters 71 and 72 may be of any suitable type but are preferably of the volumetric flow recording type so as to measure the amount of fuel flowing through the respective lines-41 and 42 and to record such amounts. The lines 41 and 42 are connected to the main gas supply line 73 ahead of the meters 71 and 72.

The thermostatic switches 31 and 32 are connected in parallel to the main power supply circuit which may include the lines T and T The thermostatic switch 31 located in Zone 1 will control both the controls 29 for the damper 23 and the solenoid of the valve 51 which are connected in parallel in the circuit. The thermostatic switch 32 located in the Zone 2 will control both the controls 30 for the damper 24 and the solenoid of the valve 52 which are connected in parallel in the circuit. When either zone requires heat, the respective thermostatic switch closes the circuit to the damper controls of that zone to open the damper in the duct to supply heat and simultaneously actuates the solenoid of the fuel supply valve for that zone and supplies fuel to the furnace 10.

With this system, assuming that the thermostatic switch 31 in Zone 1 calls for heat, the switch closes to energize the damper motor 26 and thereby open the damper valve 23 in the duct 21 leading from the furnace to Zone 1, and to simultaneously energize the fluid fuel flow control valve '51 associated with the branch inlet line 41 for the Zone 1, to permit fuel to flow into the manifold chamber 38 and then through the conduit 12 to the burner'll. Such fluid fuel which flows through the line 41 from the main supply line 73 to the burner 11 is recorded by the meter 71 associated with that branch inlet line 41. In the event that Zone 2 requires heat, the thermostatic switch 32, associated therewith, closes to actuate the damper motor 28 to cause it to open the valve 24 in the duct 22 which leads from the furnace 10 to the Zone 2, and to simultaneously actuate the solenoid of the fuel control valve 52 interposed in the inlet branch line 42, to permit the flow of fuel through the line 42 into the manifold chamber 38 and then to the burner 11. The fuel flowing from the main supply line 731 through the line 42 is metered and recorded by the meter 72 associated with the line 42. The thermostats 31 and 32 for both Zones 1 and 2 may close simultaneously and then the fuel will be supplied at the same time through both lines 41 and 42 into the chamber 38 and then to the burner 11. Thus, the amounts of fuel utilized in the heating of the respective zones may be substantially accurately metered and recorded so that they may be -charged fairly to the users of the diflferent zones.

Although I have described my invention as being applicable to a heating system, it is to be understood that it could be applied to other types of air-conditioning systems which have various zones to be controlled by supplying temperature influencing medium thereto. My invention involves the supplying of said temperature influencing medium to the system by means of a common fluid fuel controlled unit in accordance with the requirements of the various zones by means of individual fuel conduits provided for each zone, a valve being interposed in each fuel conduit for controlling the flow of fuel therefrom to said unit, and means being provided for controlling each valve in accordance with the requirements of a particular zone and for metering the flow of fuel from each of said individual fuel conduits.

According to the provisions of the patent statutes, the principles of this invention have been explained and have been illustrated and described in what is now considered to represent the best embodiment. However, it is to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

Having thus described my invention, what I claim is:

1. In combination with a system having various zones in which the temperature is to be controlled by supplying temperature influencing medium thereto, a common fluid fuel controlled unit connected to the various zones for supplying said temperature influencing medium to the various zones, means connected to said unit for supplying fluid fuel to said unit to operate it to supply said temperature influencing medium in accordance with the requirements of the various zones, said means including an individual fuel conduit for each zone which leads to said unit and is connected thereto, a valve in each fuel conduit for controlling the flow of fuel therefrom to said unit, means in each zone responsive to temperature in such zone and con- :nected to the valve for such zone conduit for controlling the valve'in accordance with the requirements of such zone, and a meter connected to each fuel conduit ahead of said valve for measuring the amount of fuel supplied .therefrom to said unit.

2. The combination of claim 1 in which the means for controlling each valve is an electro-responsive means operatively connected to the valve and the temperature responsive means is an electro-switch located in the zone to be controlled by said valve and operatively connected to said electro-responsive means.

3. The combination of claim 1 in which the valve is an electromagnetic valve and said temperature responsive -,means is a thermostat in the zone to be controlled by said valve.

4. The combination of claim 1 in which the means for supplying fuel to the unit comprises a manifold having an outlet connected to said unit, each of said individual fuel conduits connecting to said manifold.

5. The combination of clfiim 4 including a pressure regulator in each of said fuel conduits ahead of the control valve therein and between the meter and the valve individual fuel conduits from points between said valves and said regulators to the pilot burner.

7. A system having various zones in which the temperature is to be controlled by supplying temperature influencing medium thereto and including means for supplying said temperature influencing medium to the various zones and connected to said zones; a common fluid fuel controlled unit connected to said means, second means connected to said unit for supplying fluid fuel to said unit in accordance with the requirements of the various zones, said second means including an individual fuel conduit for each zone which leads to said unit, a valve for each fuel conduit for controlling the flow of fuel therefrom to said unit, means in each zone responsive to temperature in :such zone and connected to the valve for such zone conduit for controlling the valve in accordance with the rethe control valve therein.

9. The combination of claim 8 including a manifold having a-main outlet connected to said unit, all of said individual fuel conduits leading into said manifold.

10. The combination of claim 9 in which the unit includes a main burner and a pilot burner, the main outlet of the manifold being connected to said main burner, said manifold having a pilot burner supply chamber connected to said pilot burner, and pilot burner supply conduits leading from each of the said individual fuel conduits to the pilot burner supply chamber.

References Cited in the file of this patent UNITED STATES PATENTS 

